Obviously, having only an engineering degree, I am not as much of an expert as some of the negative posters.
Let's see: Bus fires: Yeah, they happen. Engines are not infallible and even timely maintenance cannot and will not prevent breakdowns. Sorry, tinkerbell is not a mechanic. They do not completely disassemble engines at every check...to expensive, so you can't see internal parts wearing.
Someone mentioned the fire extinguishers on buses and cars...they do not exist for cars and may only be required on public transportation to allow a little extra time for passengers to escape. Sorry, again us stupid engineers can't forsee or prevent everything.
Expand the monorail? First; it's very expensive to build and to run. Second; it's fun, but not a very efficient way to move passengers. Buses can be moved around the property much easier. Large crowd? Send extra buses. Hard to send extra monorails when they pretty much are operating in safety zones that would fill most of the beam.
What would I do? I'd add some light rail in places where we are moving high volumes of people: Like from TTC to Downtown Disney? Also, I would look at a new section of monorail beam...maybe Epcot to Studio or DTD? You want to build a following on both ends.:xmas: